The "3R" principle of animal experiment is: 1. Reduction refers to the scientific method of obtaining the same amount of experimental data with a small number of animals or obtaining more experimental data with a certain number of ground animals in scientific research. 2. Substitution refers to using other methods instead of animals to carry out experiments or other research topics in order to achieve some experimental purpose. Or it is a scientific method to replace conscious living vertebrates with unconscious experimental materials. 3. Optimization refers to treating animals well and improving their welfare by improving conditions on the basis of scientific principles.

Animal experiment refers to scientific research with animals in the laboratory in order to gain new knowledge about biology and medicine or solve specific problems. Animal experiments must be conducted by or under the guidance of trained personnel with a research degree or professional technical ability.

The ultimate goal of the development of experimental animal science is to study the life phenomenon of animals themselves, and then apply it to human beings, explore the mystery of human life, control human diseases and aging, and prolong human life. With the rapid development of medical biological sciences, people realize that public hazards have not only become a major social problem for food, population and the elderly, but also related to the survival of animals living on the earth, such as industrial hazards, food hazards, drug toxicity and other issues that directly affect human health.

Finally, it is necessary to clarify the solution through animal experiments (including the establishment of animal disease models, etc.). Therefore, the importance of experimental animal science, especially experimental animals, is increasingly recognized. It has always been regarded as the pillar of human pursuit of a happy life, so experimental animal science is also called life science.

For this reason, advanced countries attach great importance to the development of experimental animal science, and their economic materials and technical strength can almost be compared with the development of atomic energy science, and its significance can be imagined. At present, it cannot be replaced by other methods. Experimental animal science has become an inseparable part of modern science and technology and has formed an independent comprehensive basic science category.

The importance of this science lies in that, on the one hand, as an important means of scientific research, it directly affects the establishment and level of research results in many fields; On the other hand, as a science, its perfection and development will bring many fields of research into a new situation. Therefore, the importance of experimental animal science and technology can be summarized in the following three sentences: it is an important part of modern science and technology, the foundation and condition of life science, and an important symbol to measure the scientific research level of a country or a scientific research unit.

Experimental animal science is accompanied by biomedical science and formed through a long process of animal experiments. However, with the rapid development of experimental animal science, the research value of experimental animals is not limited to biological science, but also closely linked with scientific experimental research in many fields, which has become an indispensable condition to ensure modern scientific experimental research. In many scientific research fields, experimental animals play a very important role in safety test, effect test and standard test.